Automatic spring tensioner for tents



Oct. 29, 1957 E. E. AMES 2,311,154

AUTOMATIC SPRING TENSIONER F OR TENTS Filed Nov. 16, 1955 I INVENTOR.flown/2o E. AMEs Unite A Harris Neville Co., San Francisco, Calif., acorporation of California 7 Application November 16, 1953, Serial No.392,174

1 Claim. (Cl. 135-3) This invention relates to new and usefulimprovements in automatic spring tensioner for tents and has particularapplication in connection with umbrella-type tents wherein a center poleis provided from which radially project substantially horizontalspreaders which engage the corners of the tent to apply tension thereto.

It is well known that adjustment or compensation of tension is requiredas the canvas of a tent expands and contracts with changes in weatherconditions and stretching of the fabric after use. The present inventionis concerned with an automatic means for maintaining the canvas at aproper degree of tension despite changes in conditions which wouldotherwise affect the same.

One of the features of the present invention is the provision of aspring associated with a tensioner arm so positioned that the force ofthe spring is applied to the tent canvas to maintain the canvas tight atall times. The provision of such a spring requires no manual adjustmentas the conditions affecting the tension of the tent vary.

Other objects of the present invention will become apparent upon readingthefollowing specification and referring to the accompanying drawings inwhich similar characters of reference represent corresponding parts ineach of the several views.

In the drawings:

Fig. 1 is a vertical mid-section through a tent in which the presentinvention is installed.

Fig. 2 is a horizontal section taken substantially along the line 22 ofFig. 1.

Fig. 3 is an enlarged detail of the tensioner which is the subject ofthis invention.

A conventional umbrella-type tent employs a vertical center pole 11which is suitably imbedded in the ground. Four downwardly slanted roofsections 12 made of canvas come together at the center of the tent andare maintained in elevated position by reason of a point 13 on the topof the center pole 11 passing through a hole 14 in the center, or otherconvenient means. The roof sections 12 are joined to four wall panels 16which depend generally vertically from the outer edges of the roofsections 12. In the accompanying drawings the tent is shown as havingfour roof sections 12 and four wall sections 16 but it will beunderstood tha the number of such sections is subject to considerablevariation depending upon the design of the tent.

In order to support the roof and Wails under tension and in properposition and to give the tent a trim appearance, tensioners 21 areemployed. Generally, such tensioners are mounted on a sliding ferrule 22on the tent pole 11 and project radially outwardly from the tent pole tothe four corners at which the roof and side sections coincide. Byadjusting the elevation of the ferrule 22 relative to the tent pole, thehorizontal component of the tensioner may be regulated and accordingly,the ferrule is initially placed in proper position to supply therequired tension on the corners of the tent which 2 V is required. Whenthe ferrule 22 is once so positioned a thumb-screw 23 or other lockingdevice may be em ployed to holdthe ferrule in position and prevent itfrom sliding up or down on the tent pole. Adjustment of the position ofthe ferrule is somewhat diflicult and it is undesirable that frequentadjustment be made. Therefore, the present invention has for one of itsobjects an auto matic adjustment of the tension applied to the canvas bythe tensioner 21 as the conditions affecting the expansion andcontraction of the canvas change. Accordingly, a radially projectingrigid rod 26 of metal is provided and is hinged to the ferrule 22.Various means may be ensployed to hinge the tensioner to the ferrule; asshown in the accompanying drawings, the inner end of the tensioner rod26 is flattened as indicated by reference numeral 27 and apertured withhole 28. A pair of radially projecting cars 29 is formed on the ferrule22 in association with each of the tensioners 21. Thus, four pairs ofears 29 are employed as shown in Fig. 2 for a four-sided tent. A rivet31 passes through apertures in the ears 29 and also through the aperture28. This arrangement provides for swinging movement of the rod 26 in avertical plane about rivet 31.

The outer end of the rod 26 engages the tent wall at the intersection ofthe wall and the roof sections 16 and 12. For such purpose, a hole isformed in the canvas of the wall 16 and preferably a reinforcement 32such as a metal grommet or other conventional reinforcing means isinstalled around the edges of the hole. The outer end of the rod 26projects through the reinforcement 32. In order to provide tensionagainst the tent wall 16 a coil spring 36 is installed around the outerend of the rod 26. First and second washers 37 and 38 are placed at theinner and outer ends of the spring 36, respectively, the outer washer 38bearing against the side 16 and transmitting the pressure exerted by thespring 36 against the tent wall. The inner washer 37 is held in positionby means of lugs 39 formed in the rod or any other suitable means forrestricting inward movement of the spring 36. To prevent dislodgement ofthe spring 36 and washers 37 and 38 when the tensioncr is not in use,another pair of lugs 41 is formed adjacent the extreme outer end of therod 26, the outer lugs preventing the washers and spring from coming offthe end of the rod. However, the outer lugs 41 are small enough so thatthey will fit through the grommet 32 or other reinforcement in the tentwall but at the same time are large enough so as to prevent the washer38 from being dislodged.

In use, the tent pole 11 is inserted through the hole in the top of thetent and the pole is then placed in vertical position. At this stage ofthe operation the ferrule 22 is lowered and the rods 26 are notpositioned in engagement with the tent wall. After the center pole 11 iserect, the ferrule 22 is raised into a position below its final positionand at this time the ends of the rods 26 are inserted through thereinforcements 32 in the corners of the tent. The ferrule 22 is thenraised into proper position so that proper initial tension is impartedto the canvas and when this position is found, the wing nut 23 or otherlocking means is tightened to hold the ferrule at that position. Whenthe ferrule is properly located, the springs 36 impart a desired amountof tension to the tent walls. As climatic conditions and otherconditions affecting the canvas result in expansion or contraction ofthe canvas the expansion and contraction is compensated by expansion andcontraction of springs 36 without the necessity of adjusting theposition of the ferrule 22 or making any other manual adjustment of thetensioning arms 21.

Although I have described my invention in some detail by way ofillustration and example for purposes of clarity of understanding, it isunderstood that certain changesand modifications may be practiced withinthe spirit of the invention and scope of the appended claim.

What is claimed is: I 1 Means for automatically adjustingpthe tension ofa tent ateave-line corners formed with grommet apertures comprisingaferrule arranged forsliding movement on a tent pole, means for lockingsaidf errule in position relative to said pole, a plurality of rods,said rods being of'substantially uniform thickness throughout fromadjacent their inner ends to their outer ends, a corresponding pluralityof means for articulately connecting said rods and said ferrule forvertical swinging movement of said rods, a plurality of helical springs,each said spring being carried by its corresponding rod adjacent theouter end thereof, said outer ends of said ro ds being oi saiduniform 151,583,831

thickness, a first washer around each said rod at the inner end of saidspring, means for restraining inward movement of said first washer, asecond washer around each said rod at the outer end of said spring andbiased outwardly thereby, and lug means mounted on said rods restrainingoutward movement of said second washer, said lug means and said rodsbeing smaller than the grommet apertures of said tent and said secondwasher being larger than the grommet apertures.

References Cited in the file of this patent UNITED STATES PATENTS Dunn-i Apr. 10, 1923 Hoigaard May 11, 1926

